This invention relates generally to agricultural combines, and more particularly, to a foldable chaff pan for disposition rearwardly of cleaning apparatus of an agricultural combine for conveying chaff from the cleaning apparatus to a chopper and/or spreader, the pan being connected to the cleaning apparatus for oscillation therewith and being foldable between a deployed position for conveying the chaff, and a retracted position for allowing access to the cleaning apparatus and the chopper and spreader for ease of maintenance, service and inspection thereof.
Currently, combines typically include a straw chopper and/or straw spreader for disposing of straw separated from the harvested crop onto the crop field. In addition, some combines have a chaff spreader for spreading the chaff separated from the grain by the cleaning apparatus or system. It is desirable to provide the chaff spreading function, however, it is also desired to eliminate the additional chaff spreader apparatus due to the cost, weight, space, and maintenance requirements thereof. One approach for eliminating the chaff spreader is to route the chaff blown and discharged by the cleaning apparatus into the straw chopper and/or straw spreader so as to be chopped and/or spread over the field thereby. This can be done by mounting the chopper and/or spreader directly behind the chaff discharge end of the cleaning apparatus. However, a shortcoming of this location is that it makes access to the cleaning apparatus for service, maintenance, and inspection difficult, which is undesirable. As an alternative, the chopper and/or spreader can be spaced rearwardly of the cleaning apparatus to provide an access space or gap therebetween for service and the like. However, this space or gap presents a problem as it must be crossed or bridged by the chaff enroute to the chopper and/or spreader. The chaff is typically carried rearwardly by a flow of air blown upwardly through the cleaning apparatus, and to enclose this space to contain the chaff containing air flow and direct it to the chopper and/or spreader, a pan or other enclosure can be used. It is known to mount such pans to the frame or other enclosures of the combine, or to the cleaning apparatus itself, and for the pan or enclosure to be foldable between an operational position and an open position. However, pans or enclosures attached to the combine frame but not to the cleaning apparatus have the disadvantage that they do not provide a continuous path from the cleaning apparatus to the chopper and/or spreader and do not vibrate or oscillate with the cleaning apparatus. Pans attached to the cleaning apparatus will oscillate therewith, but if supported only by the cleaning apparatus place loads thereon which can degrade the operation thereof. Thus, what is sought is a pan for conveying chaff to a chopper and/or spreader located spacedly behind the cleaning apparatus of a combine, that is attachable to the cleaning apparatus for vibration or oscillation therewith, but without unduly loading it, and which is easily and conveniently repositionable or movable for allowing access to the cleaning apparatus and the chopper and/or spreader.
Additionally, some combines have cleaning apparatus which are self-leveling, that is, they pivot or tilt at least sidewardly to compensate for tilting of the combine as it moves across the sides of hills and the like. Thus, it is also sought that a pan for bridging the space between the cleaning apparatus and the chopper and/or spreader be able to pivot or tilt with the cleaning apparatus.
What is disclosed is a foldable chaff pan for attachment to an oscillating or vibrating element of a cleaning apparatus or system of an agricultural combine for oscillation therewith for conveying chaff from the oscillating element to a non-oscillating chopper or spreader mounted to a fixed frame of the combine, which chaff pan overcomes many of the shortcomings discussed above, including avoiding loading of the cleaning apparatus or system so as not to degrade the operation thereof, and which is sidewardly tiltable with the cleaning apparatus or system, if so capable. The foldable chaff pan has a surface for receiving the chaff positionable in a first position adjacent to the oscillating element of the cleaning apparatus which can be, for instance, a chaffer, a sieve, a frame or rails supporting the same, or the like, for receiving the chaff therefrom, a pivoting element for connecting the pan to the oscillating element for oscillation therewith and pivotal movement relative thereto about a generally horizontal axis between the first position and a second position angularly related to and beneath the first position, and a linkage arrangement for connecting the pan to the fixed frame such that the pan is largely supported by the fixed frame, the linkage arrangement including a shaker arm connected to the pan and locatable in a support position for supporting the pan in the first position while allowing the pan to oscillate with the oscillating element relative to the linkage arrangement, and the linkage arrangement including a releasable spring element holding the shaker arm in the support position and releasable to allow the shaker arm to move from the support position to another position to allow the pan to be folded to the second position to allow easier access to the cleaning apparatus.
The shaker arm of the foldable chaff preferably includes a pivotal connection to the pan and a pivotal connection to another element of the linkage arrangement connected to the spring element for applying a force of the spring against the shaker arm for holding the pan in the first position. Additionally, according to one aspect of the invention, the spring element is positionable in a first orientation for exerting a force through the shaker arm against the pan for holding the pan in the first position, and is positionable in a second orientation for exerting a force through the shaker arm against the pan for holding the pan in the second position.
When the cleaning apparatus is mounted for pivotal movement relative to the frame in a sidewardly direction relative to a direction of oscillation, the shaker arm of the pan can be optionally connected to the pan with an element which allows sideward movement of the pan relative thereto such that the pan can pivot sidewardly with the cleaning apparatus relative to the linkage arrangement.